One of the world's top advertising awards went this year to a campaign in which a radio station broadcast ultrasound along with its programmes to repel mosquitoes. But does it work? Definitely not, say scientists.

It was a beautifully simple idea. No more need for smelly lotions, chemical gases, smoke or rolled-up newspapers, listeners to Brazilian station Band FM were told - all you need to do to beat mosquitoes is to stick close to the radio.

The station broadcast a high-frequency 15kHz tone under its music in April this year. Inaudible to most adults, the tone was supposed to repel mosquitoes, allowing listeners to relax in the open air without fear of getting bitten.

The broadcasts were sponsored by the magazine GoOutside, as part of a radio marketing campaign which went on to win the Grand Prix in the radio category at the Cannes Lions in June - perhaps the most prestigious awards in advertising.

Interesting. I'd always thought there were studies showing the effect of ultrasound. I personally never liked those devices since I'm not deaf enough to not be annoyed by the high pitched noise.
Moreover, I thought radio (ultra short wave) transmitted frequencies between around 100Hz and 11kHz, but I couldn't find that anywhere. Does anyone know the exact range?_________________Kali Ma
Now it's autumn of the aeons
Dance with your sword
Now it's time for the harvest

Interesting. I'd always thought there were studies showing the effect of ultrasound. I personally never liked those devices since I'm not deaf enough to not be annoyed by the high pitched noise.
Moreover, I thought radio (ultra short wave) transmitted frequencies between around 100Hz and 11kHz, but I couldn't find that anywhere. Does anyone know the exact range?

Yeah, it's like citronella candles. Some tests say they are useless, but I use them here and they work fine. It depends on the conditions they are tested under I suppose, my backyard is not a laboratory environment and most laboratories are not right next to very swampy brackish waters. The mosquitoes here are not cooped up and then let loose in a small controlled environment.

They also sell ultrasonic devices to deter kangaroos from hopping in front of ones car during a dusk car cruise. I suspect they work on a placebo basis. That is: If one is shit scared and gouging holes in the sides of the steering wheel with ones fingernails then one is probably going to be too frazzled to avoid a interspecies collision.

Moreover, I thought radio (ultra short wave) transmitted frequencies between around 100Hz and 11kHz, but I couldn't find that anywhere. Does anyone know the exact range?

The military uses frequencies all the way down to about 3 Hz, if you can imagine, up to (and into, actually) what is considered infrared._________________Deja Moo: the feeling that you've heard this bull before

That's not what I meant. Radio frequencies of ultra short wave are (in Germany) between 87 and 108MHz. I meant the audio signal that radio waves carry. I think I read that you can only have sound in a certain, quite narrow spectrum over (analogue) radio, ranging from somewhere around 100Hz (so no really deep basses) to around 11kHz._________________Kali Ma
Now it's autumn of the aeons
Dance with your sword
Now it's time for the harvest

That's not what I meant. Radio frequencies of ultra short wave are (in Germany) between 87 and 108MHz. I meant the audio signal that radio waves carry. I think I read that you can only have sound in a certain, quite narrow spectrum over (analogue) radio, ranging from somewhere around 100Hz (so no really deep basses) to around 11kHz.

Yeah, that would make sense. I know that VLF, which is used by HAM radio, starts at 30 kHz, so I would suspect that's usable for voice, but not necessarily for music. I don't know much about it, but I'm pretty sure a wide range of the radio spectrum can carry audio. Other factors are probably involved beyond the basic frequencies and wavelengths, such as carrier frequencies, but now I'm talking over my head. This is where we need an engineer. Or maybe just somebody omniscient, like Akkara, if anybody knows how to conjure him.

My experience with mosquitoes has been that they're attracted by smell, although I have my doubts that it's just carbon dioxide like I've read. The longer you stay in one spot, the more of them show up. That's consistent with CO2 attraction. But, I've also noticed that they seem to go after people who have not been outside more than people who have been outside (almost to the point where if you've been in the woods for a couple of days, they don't come after you at all). That's not consistent with it being just CO2.

Also, it seems like most blood-eating insects (mosquitoes, black flies, horse flies, deer flies, etc.), go after the people who are the most freaked out by them. That could just be "measurement bias" because they're calling attention to themselves, but I don't think that's all there is to it. I think they're attracted by distress pheromones or something.

Then there's the obvious stuff, too. If you walk on a moist forest path in a T-shirt and shorts near the slow-moving edge of a shady brook in early Summer around dusk and you stop to have a conversation, then you can fully expect to be eaten alive (i.e., bitten dozens of times per minute)._________________Deja Moo: the feeling that you've heard this bull before

One of the world's top advertising awards went this year to a campaign in which a radio station broadcast ultrasound along with its programmes to repel mosquitoes. But does it work? Definitely not, say scientists.

It was a beautifully simple idea. No more need for smelly lotions, chemical gases, smoke or rolled-up newspapers, listeners to Brazilian station Band FM were told - all you need to do to beat mosquitoes is to stick close to the radio.

The station broadcast a high-frequency 15kHz tone under its music in April this year. Inaudible to most adults, the tone was supposed to repel mosquitoes, allowing listeners to relax in the open air without fear of getting bitten.

The broadcasts were sponsored by the magazine GoOutside, as part of a radio marketing campaign which went on to win the Grand Prix in the radio category at the Cannes Lions in June - perhaps the most prestigious awards in advertising.

There's just one problem. Scientists say it's nonsense.

15k is not ultrasound and the only affect on the environment: damages the ears of children.

Well done, idiots!_________________

AidanJT wrote:

Libertardian denial of reality is wholly unimpressive and unconvincing, and simply serves to demonstrate what a bunch of delusional fools they all are.

Boy, one could get rich just with variations on this theme. "Hey, women. Use T-Mobile wireless! Our patented circuitry surrounds your face with wrinkle-reducing electromagnetic waves while you use your phone!" "Hey, men! Watch Spike TV! We broadcast subliminal messages clinicly proven in independent studies* to make your penis larger!"

People might not go for it here, but I bet you could get rich with that in most East Asian countries and France._________________Deja Moo: the feeling that you've heard this bull before

Boy, one could get rich just with variations on this theme. "Hey, women. Use T-Mobile wireless! Our patented circuitry surrounds your face with wrinkle-reducing electromagnetic waves while you use your phone!" "Hey, men! Watch Spike TV! We broadcast subliminal messages clinicly proven in independent studies* to make your penis larger!"

People might not go for it here, but I bet you could get rich with that in most East Asian countries and France.

East Asia probably but not France. If you had ever dealt with frenchies you would know that all french 'males' think that their cock is the biggest, greatest and best dick in the universe and impossible to improve while french 'females' think that they are just perfect the way they are. Of course, some make up and hair styling - but just to underline their utter flawlessness. Those are the same reasons why they abhore shaving - or soap._________________

AidanJT wrote:

Libertardian denial of reality is wholly unimpressive and unconvincing, and simply serves to demonstrate what a bunch of delusional fools they all are.

I read the average number of times per week they brush their teeth has finally broken the seemingly impenetrable "three barrier", thanks to EU-sponsored public service announcements._________________Deja Moo: the feeling that you've heard this bull before

I have lived almost half my life in the tropics.
Mosquitoes galore.
Their are many misconceptions about these pests.
At night they'll avoid well lighted areas.
Lots of people think they are attracted by light,wrong.
That's why dark clothes will attract them more than white.
Going to bed you check the bedroom,none.
As soon as you turn off the light they'll attack,they were in the room alright but sitting on a dark spot.
I often made use of mosquito spirals (made in China) green pressed stuff.
Seems forbidden in Europe,never hurt me though.
You light one and the smoke is an excellent repellent,they really work.
High frequency sound is bullshit,citronella based oils work but I hate to apply it.
Gerard._________________To install Gentoo I use sysrescuecd.Based on Gentoo,has firefox to browse Gentoo docs and mc to browse (and edit) files.
The same disk can be used for 32 and 64 bit installs.
You can follow the Handbook verbatim.
http://www.sysresccd.org/Download